An MH-65 Dolphin helicopter crew assigned to Coast Guard Air Station Barbers Point in Kapolei, Hawaii, flies over a flooded neighborhood in Waialua on the north shore of Oahu March 20, 2026. The Honolulu Department of Emergency Management issued mandatory evacuations for communities in Waialua and Haleiwa following heavy rainfall and flooding across Oahu. (U.S. Coast Guard photo, courtesy Air Station Barbers Point)

(BIVN) – A Flood Watch continues for the entire State of Hawaiʻi, as another kona low is bringing heavy rains to the islands, just one week after a previous storm produced damaging wind and rains. 

So far, Oʻahu has borne the brunt of this second kona low, and has been under a continuous state of flash flooding. 

Hawaiʻi island is expected to eventually see some heavy rain from this storm, although not to the degree of Oʻahu and Maui. 

A Winter Storm Watch is also in effect for Hawaiʻi island summits. Total snow accumulations up to 10 inches will be possible atop Maunakea and Mauna Loa, with winds gusting as high as 70 mph.

From the National Weather Service forecast discussion posted on Saturday morning:

This mornings satellite imagery showers a long lived smaller scale low level convergence band slowly drifting eastward through Maui County. The heaviest showers and thunderstorms are currently developing along this convergence band within 50 miles north and south of Molokai early this morning. This band will continue the be the primary driver of heavy rain over Maui County today as it slowly drifts eastward into Maui later this morning. For Oahu, a broad band of enhanced clouds are moving towards Oahu and are consolidating along a new low level smaller scale convergence band. Showers are already increasing across the island with deeper. cloud heights rising into the 25,000 to 30,000 foot range based on satellite cloud top temperatures and may lead increasing moderate to heavy showers over Oahu. Enhanced showers are also shown on radar imagery developing just upstream of Kauai and the Big Island. We continue to watch this fluid situation closely as the heaviest rainfall impacts will evolve on an hour by hour timeline. Stay vigilant this weekend.

Focusing on the larger scale for a moment, we continue to see two surface lows within the larger kona low structure drifting towards the northeast passing just north of the island of Kauai. The highest upper level forcing from this kona low will develop over Oahu and the islands of Maui County into Sunday. The Big Island will likely see additional large scale forcing by early Sunday morning into Monday with this system.

By Monday, the pattern begins to change for the western islands as cool northeasterly trades blow into Kauai and Oahu. Returning trade winds will signal improving weather trends as the deep moisture and unstable atmosphere will be driven towards the south, away from the islands. By Tuesday, deep unstable moisture will clear up over Maui County and the Big Island of Hawaii with improving weather trends. Upper level troughing will linger across the Hawaii region next week. However, heavier showers will diminish as the weather pattern shifts back to a more typical wet trade wind weather pattern. Passing light to moderate showers will favor the typical windward and mountain areas with this easterly trade wind pattern lasting through next weekend.